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<br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />riparian <br />packaged <br />either a <br />district. <br /> <br />land owners. Any cleanup work <br />with a plan for maintenance of <br />regulated maintenance by the owners <br /> <br />should be <br />the channel <br />or a special <br /> <br />CALCULATIONS <br /> <br />The volume <br />simplified <br />surveyed to <br />of the 100 <br />determine a <br />cross section <br />river and <br />calculated. <br /> <br />of the material to be moved was calculated by a <br />end area method. The reach under calculation was <br />determine the average natural width and average depth <br />year flood line. This information was used to <br />cross section that would pass the 100 year storm. The <br />was then overlayed several typical sections of the <br />a average amount of material to be removed was <br /> <br />This method of calculation using the average cross section has <br />given a conservative estimate of the cost for removal of the sand <br />and gravel bars. a much closer estimate could be achieved by an <br />analysis of 100 foot sections of the river. However, this <br />accuracy was not necessary for this cost estimate. <br /> <br />RIVER AND FLOOD DATA <br /> <br />Uncompahgre River <br /> <br />Length - 49,800 feet - the center <br />River from the Delta/Montrose <br />Gunnison River at Delta. <br /> <br />line length of the Uncompahgre <br />County line to confluence with the <br /> <br />Flow - 5000 cfs - 100 year flood flow at the confluence with the <br />Gunnison River <br /> <br />Roughness Coefficient 0.035 - main channel <br />- 0.040 - 0.060 - overbank <br /> <br />Average Slope - 0.51% average from the confluence with the <br />Gunnison River to the Delta/Montrose County Line. <br /> <br />Depth of 100 year flood from centerline of channel - 5 to 8 feet. <br /> <br />width and depth of channel to maintain a 100 year flood of 5,000 <br />cfs at the average slope (from Mannings Formula). <br /> <br />Channel <br />Depth <br /> <br />Channel <br />width <br /> <br />5 <br />6 <br />7 <br />8 <br /> <br />120 <br />90 <br />70 <br />60 <br /> <br />C-3 <br />